Field of Invention
The present invention relates to a molding system and method. More particularly, the present invention relates to a molding system and method for directly gas-cooling a molding object.
Description of Related Art
The traditional plastic injection molding process comprises the following steps: at first, the plastic material is fed into the feeding tube of the injection molding machine to plasticize the plastic material into molten resin and then the following steps in sequence. The forming mold is closed, the molten resin is injected into the cavity of the forming mold, pressure is held by the injection molding machine, the forming mold is cooled circularly, the forming mold is opened, the finished product is knocked out, and then the finished product is output. Another traditional thermoforming process comprises the steps as follows: the material (composite material) is first placed into the mold and is heated by raising the temperature continuously followed by closing the mold, increasing pressure, cooling, releasing pressure, opening the mold in sequence, and then the finished product is output.
The traditional mold cooling method is to dispose a plurality of circulating pipelines in which water or oil acts as a medium inside the mold. The water or oil circulates in the interior of the mold through a mold temperature controller so as to heat or cool the mold. One of the methods to achieve the circular cooling step of the forming mold is to use cooling water as a cooling medium so as to cool the forming mold. In greater detail, circulation water channels are buried in the forming mold body so that cooling water flows circularly in the forming mold body along the circulation water channels through the mold temperature controller. In this manner, heat of the forming mold is carried away, and heat energy of the finished product inside the forming mold is therefore carried away indirectly.
However, utilizing cooling water as a cooling medium to cool the forming mold has the following disadvantages. First, in order to ensure that the cooling water can flow circularly in the forming mold, vendors are required to additionally provide relevant equipment, such as a pump, a fan motor of cooling tower, a mold temperature controller. In addition, since the heat energy in the mold core needs to be carried away indirectly through such equipment and the water channels buried in the mold core, not only is the cooling efficiency poor to lengthen the cooling time, but the entire molding cycle of the finished product is also lengthened, thus affecting production efficiency.
In addition, when cooling water flows circularly in the forming mold for a long time, the cooling water may generate scales having a specific thickness on inner walls of the circulation water channels. The scales isolate the cooling water from the inner walls of the circulation water channels that leads to decline in cooling performance. In additional to that, when the cooling water at a low temperature flows circularly in the forming mold, condensed water droplets will be generated on the inner surface of the cavity of the forming mold due to the low-temperature cooling water, thus affecting the molding quality of the finished product.
For the forgoing reasons, there is a need to resolve the above-mentioned inconveniences and shortcomings by providing a molding system and method for directly gas-cooling a molding object, which is also an objective that the relevant industry is eager to achieve.